Apparatus for burning waste material



Jan. 9, 1951 T. R. KOMLINE 2,537,457

APPARATUS FOR BURNING WASTE MATERIAL Filed May 28, 1946 I I I \1/ A 26 h13 Z9 oo o o 000 j 27 f7 30 1 l l 30 ,IIJ 2 o g g 4 4 J3 INVENTOR.THOMAS R. KOMLINE A T TORNE Y Patented Jan. 9, 1951 APPARATUS FORBURNING WASTE MATERIAL Thomas R. Komline, Glen Rock, N. J., assignor toKomline-Sanderson Engineering Corporation, Glen Rock, N. J a corporationof New Jersey Application May 28,1946, Serial No. 672,773 (o1. 110-8) 16Claims, 1

This application is a continuation-in-part of my application Ser. No.540,819, filed June 17, 1944, for Sludge Burner, which has-now beenabandoned.

This invention relates to apparatus for and method of burning wastematerial. Its object is to provide a means and way for incineratingsewage sludge or other similar waste matter. More particularly, thepurpose of the invention is to incinerate such material as a continuousprocess, utilizing the resultant heat and gases of combustion in anormally closed cycle to heat and dry following material prior to thecombustion of the latter. This operation is based upon the fact thatmaterial like sewage sludge, which includes up to 70% moisture content,contains combustible solids in a quantity having enough calorific valueto support its own combustion.

An additional object is to provide a structure which comprises, incombination with a chamber, a centrifugal atomizer, a funnel-shaped feedspout into which the atomizer discharges finely comminuted sludge or thelike, means to' withdraw hot gases of combustion from the chamber and todischarge such gases into the feed spout for heat interchange with thesprayed sludge, and to force-feed the resulting mixture through the feedspout as a high-velocity stream, an instrumentality located intermediatethe ends of the chamber ad acent the discharge end of the feed spoutwhich is arranged to deflect the lighter constituents of the stream,including the major portion of the spent gases which have been used fordrying the material, which instrumentality includes a tuyere forintroducing fresh air across the flow of the stream, and a heatedportion through which the heavier constituents of the stream pass andare ignited.

Other objects of the invention are to produce a simple, inexpensive andpractical device and anovel method of operation which is effective andefficient for the purposes for which it is designed. These objects areaccomplished by means of such a structure and relative arrangement ofparts as are fully described in the following specification, and thenovel features of which are defined in claims.

The figure of the drawing is'a sectional elevation of a burner which ismade accordingto and embodies this invention.

This apparatus comprises a chamber having a substantially cylindricalbody I having an inverted conical hopper 2 forming the lower endthereof. The body and hopper are provided with a refractory lining 3 andare supported in At. its .upper end" the body. is closed by a struc-;

ture whichforms an annular passageway 5, generally in'the-formof aninverted truncated cone,

which is formed between a top plate 6 and a bottom plate 1.. Acentrifugal atomizer it is mounted on the 'topplate ii,uwhich has acentral opening 8, throughtwhich theldistributor 9 of the atomizer Inprojects into the lower end. of thepassageway 5. @This centrifugalatomizer is.shoWn in detail iin my U. S. Patent-No. 2,292,572, issuedAugust 11,---l9i2;i'and the specific construction of ospart ofthe.present inventhis device .f'o'r tiongli. in J.

Then-distributor "in the lower part .of the passageway t'lextendsdownwardly into the upper e'ndof a funnel-shaped feed spout I l', whichcommunicates at its upper end withthe passage ways... centrally tliroughthe bottom plate 1. The upper end of this feed spout islof aconsiderably largerdiameter than that of the distributor '9," :Sludge isfed -to the centrifugal atomizer ill-'thtougl'itaieed pipe 12.Immediately below the funnel-shaped feed-spout H is an instrument'alitywhichincludes an upwardly-opening bowl l3 having-anoutwardly-flaringcurveddefiecting sur'facei an'd h'as a tuyere embedded in it, whichdischarges into the bowl through jets l4. Air unde'rpress'ure fed-to thejets through an 'annular manifold l5 included. in the bowl, and a--co'nduit lt which leads from an-air pump -l1"outside' of the chamber;-The length of the conduit within-the chamber is such that the airpassing 'through'it heated before its discharge intothe'bowlfi JThelo'we'r-"endi of he bowl isin'open commu nicat'ion'withajcylindr'ical ignition tube 1 8, which may be' 'an -ihtegral' part ofthe bowl, and the bowl andtu inay be made of refractory ma terial.They-are" supported from the bottom of the heater b'ya ispider l9. l hedistributor 9, feed spout H, bowl l3 and tube it are relativelyconcentric, with the'bowl 13 being substantially larger at its upperend-than the adjacent lower end of the feed spout H. Intermediate theignition tube #8 and the hopper 2, the'chamber is provided with ahori-'- zontal rowof circumferentially spaced ports 20, whichcommunicate with an annular manifold 2| surrounding the lower end of thebody 'I, A suction conduit 22 leads upwardlyfrom the manifold'2i to ahigh-temperature fan or air-pressure pump-'23, ll-discharge conduit 24leads from this pressure pump to an' annular manifold 25, whichsurro'undsthepassageway 5 and communicates therewith. 26 is a conduit,which forms a communication between the interior of the body Iintermediate its ends, and the conduit 22 intermediate the manifold 2|and the pressure pump 23. A valve 21 in conduit 26 is provided forcontrolling the gaseous flow therethrough. Opposite the conduit 26another lateral conduit 28, which likewise includes aflow-control valve29. 2

Burners 3U, 30, adapted to be connected with a source (not shown) ofauxiliary fuel, project into the hopper 2 near the upper part thereof.

In operation of this apparatus, the sludge which is fed by pipe l2 intothe centrifugal atomizer i is sprayed outwardly through the distributor9 in a substantially horizontal plane in the form of a relatively finemist or fog. The heavier constituents of the material, which are ignitedas they pass through the ignition tube l8, burn in the area ofthe'chamber at the lower end of the body I and inthehopper 2-. Theseportions of the structure form its combustion space. Hot gases which aredrawn from this combustion space through ports 20 andmanifold 2i aredischarged at high velocity and relatively great quantity by thepressure pump 23. These gases are the result of combustion and arecomparatively inert. They flow inwardly from the manifold through thepassageway into the upper end of the funnel-shaped feed spout H. Whenthis occurs these hot gases are intermixed with the sprayed. sludge fromthe distributor 9, and the mixture of sludge particles and gases passdownwardly through the feed spout. ll. While. passing through the feedspout a heatinterchange occurs between the hot gases and sprayed sludge,which materially reduces the moisture content of the latter. Thereafter,the mixture is dischargedfrom thelower end of the feed spout H into thebowl 13 Due to the shape of the deflecting walls of. the bowl l3 and theresistance offered by the transverse air streams from the tuyre as theyare discharged into the bowl through the jets 14', the greater part ofthe gases and the lighter constituents of the matter carried by thegases from the. feed spout II are deflected upwardly and outwardly fromthe bowl in the directions indicated by the arrows, AA, whilesubstantially all of the sprayed dried sludge continues downwardlyadmixedwith fresh heated air from the tuyere into-and through the-tubeI8.

The burners 30, 30,;which project into the hopper or lower portion ofthe chamber, are used to heat the ignition tube. l8 to a temperatureabove the ignition temperature of the more volatile particles of thesludge.. to initiatevtheir incineration. The continued. combustion ofthe sludge as it passes through tube l8 maintains the temperature of.the tube above this self-ignition temperature of the sludge. If themoisture content of the sludge requires auxiliary heat to assurecontinued combustion, it can be provided by the burners 30, 3G.Incineration is completed in the combustion space in the lower part ofthe chamber.

The gases which escape upwardly and outwardly from the bowl I3, aspreviously described, are relatively cool and may be drawn throughlateral conduit 26 into conduit 22 to temper. the hot gases inthelatter, if necessary. The flow of these gases may be controlled by thevalve 21. The valve 29 in lateral conduit 28 may be open to the extentnecessary to permit these relatively cool gases to be-vented' from thechamber.

The ash. from the combustionin the chamber 4 falls against therefractory lining 3 of the hopper 2, which is closed at its lower end,as shown at 33. This ash collects in the lower part of the hopper in theform of a molten slag, shown at 34. Such of the incinerated matter asfalls onto the slag at 34 is cushioned thereby. A series of horizontallyaligned ports 35 vertically spaced from the lower end of the hopper 2are provided through the wall of the hopper and its lining, throughwhich this slag escapes and falls onto a receiver or carry-off conveyor,indicated diagrammatically at 32.

In the operation of this device the re-circulation of the hot spentgases of combustion is one of the essential features, as it assures hightemperature of the high-velocity stream of gases introduced in thepassageway 5 and into the feed spout ll, into which the sludge isintroduced as a spray from the distributor 9 to condition the sludge forsubsequent combustion.

Previous attempts to dry and burn sludge and the like in one structurehave been unsuccessful because of the fact that the volume of hot gasesrequired for drying have been so great that they have interfered withthe incineration of the dried material. I have found that it isnecessary to remove the greater part of these drying gases fromthemixture to be incinerated before it is ignited. Attempts to burn sewagesludge on a fuel bed have been unsuccessful, and I have found that suchmaterial can be more successfully incinerated if burned in suspensionFrom the foregoing description it will be readily seen that this devicefulfills the objects of the invention as set forth herein. The specificapparatus illustrated and described is disposed vertically, but this isnot a necessary limitation.

Various modifications in construction, mode of operation, method and useof an invention may and do occur to others, especially after benefitingfrom knowledge of such a disclosure as that herein presented, of theprinciples involved, but the invention itself is not confined to thepresent showing.

I claim:

1. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, means for withdrawing hotgases of combustion from one part of the chamber near the combustionspace and forcing said gases as a stream through the feed spout into thechamber, means for introducing finely comminuted material into thestream, an axially disposed separating instrumentality between thedischarge end of the feed spout and the combustion space for deflectinglighter constituents of the stream outwardly, and means for heating theundeflected constituents of the stream to a temperature above theirignition temperature.

2. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into the part of thechamber remote from the combustion space, means for withdrawing hotgases of combustion from one part of the chamber near the combustionspace and forcing said gases as a stream through the feed spout into thechamber, and means for introducing finely comminuted material into thestream, an axially disposed separating instrumentality between thedischarge end 9f the feed Spout and the combustion space for deflectinglighter constituents of the stream outwardly, said instrumentalitycomprising means for heating the undefiected constituents of the streamto a temperature above their ignition temperature.

3. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from thev combustion space, mean for withdrawing hotgases of cornbustion from one part of the chamber near the combustionspace and forcing said gases as a stream through the feed spout into thechamber, means for venting the chamber, means for introducing finelycomminuted material into the stream, an axially disposed open-endedcircular bowl adjacent the discharge end of the feed spout, with the endof the bow1 nearest the feed spout wider than the discharge end of the.feed spout and with the sides of the bowl converging toward its otherend, means for introducing gas containing oxygen into the stream beyondthe discharge end of the spout in directions substantially transverse tothe flow of the stream through the feed spout to cooperat with saidsides of the bowl to deflect lighter constituents of the streamoutwardly, and means for heating a part of the bowl through whichundefiected constituents of the stream pass, to a temperature above theignition temperature of said undefiected constituents.

4. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a partof thechamber remote from the combustion space, means for withdrawing hotgases of combustion from one part of the chamber near the combustionspace and forcing said gases as a stream through the feed spout into thechamber, means for venting the chamber, means for introducing finelycomminuted material into the stream, an axially disposed open-endedcircular bowl adjacent the discharge end of the feed spout, with the endof the bowl nearest the feed spout wider than the discharge end of thefeed spout and with the sides of the bowl converging toward its otherend, means for introducing gas containing oxygen into the stream throughthe sides of the bowl in directions substantially transverse to the flowof the stream through the feed spout to cooperate with said sides of thebowl to deflect lighter constituens of the stream outwardly, and meansfor heating a part of the bowl through which undefiected constituents ofthe stream pass, to a temperature above the ignition temperature of saidundefiected constituents.

5. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, means for withdrawing hotgases of combustion from one part of the chamber near the combustionspace and forcing said gases as a stream through the feed spout into thechamber, means for venting the chamber, means for introducing finelycomminuted material into the stream, an axially disposed open-endedcircular bowl adjacent the discharge end of the feed spout, with the endof the bowl nearest the feed spout wider than the discharge end of thefeed spout and with the sides of the bowl converging toward its otherend and terminating in an ignition tube, means for introducing gascontaining oxygen 7 into the stream beyond the discharge end of thespout in directions substantially transverse to the flow of the streamthrough the feed spout to cooperate with said sides of the bowl todeflect lighter constituents of the stream outwardly, and means forheating the ignition tube through which undefiected constituents of thestream pass, to a temperature above the ignition temperature of saidundefiected constituents.

6. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, means for withdrawing hotgases of comand with the sides of the bowl converging toward its otherend and terminating in an ignition tube,

' means for introducing gas containing oxygen into the stream through aplurality of angularly spaced orifices in the sides of the bowl indirections substantially transverse, to the flow of the stream throughthe feed spout to cooperate with said sides of the bowl to deflectlighter constituents of the stream outwardly, and means for heating theignition tube through which undefiected constituents of the stream pass,to a temperature above the ignition temperature of said undefiectedconstituents.

7. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed funnel-shaped feed spout projecting into apart of the chamber remote from the combustion space with its larger endoutermost, means for withdrawing hot gases of combustion from a part ofthe chamber near the combustion space and forcing said gases as a streamthrough the feed spout into the chamber, means for introducing finelcomminuted material into the stream near the larger end of the spout, an

axiall disposed separating instrumentality between the discharge end ofthe feed spout and the combustion spac for deflecting lighterconstituents of the stream outwardly, and means for heating theundefiected constituents of the stream to a temperature above theirignition temperature.

8. A burner comprising a structure forming a substantially closedchamber of circular cross I section with a combustion space'folmedtherein,

an axially disposed feed spout projecting into a part of the chamberremote from the combustion space, means for withdrawing hot gases ofcombustion from a part of the chamber near the combustion space andforcing said gases as a stream through the feed spout into the chamber,means for venting the chamber, means for intro .ducing finely comminutedmaterial into the containing oxygen into the stream through oriflees inthe sides of the bowl in directions substantially transverse to the flowof the stream through the feed spout to cooperate with said sides of thebowl to deflect lighter constituents of the stream outwardly, said meanscomprising a pressure pump outside of the chamber, and a conduit passingthrough the chamber interconnecting the pump with the orifices in thebowl, and means for heating a part of the bowl through which undeflectedconstituents of the stream pass, to a temperature above the ignitiontemperature of said undefiected constituents.

9. A burner comprising a structure forming a substantially closedchamber of circular cross section. with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, a manifold outside of thechamber in communication with the combustion space, a pressure pump, asuction conduit between the manifold and the pump, a pressure conduitbetween the pump and the feed spout, means for venting the chamber,means for introducing finely comminuted material into the stream, anaxially disposed open-ended circular bowl adjacent the discharge end ofthe feed spout, with the end of the bowl nearest the feed spout widerthan the discharge end or the feed spout and with the sides of the bowlconverging toward its other end, means for introducing gas containingoxygen into the stream through the sides or" the bowl in directionssubstantially transverse to the flow of the stream through the feedspout to cooperate with said sides of the bowl to deflect lighterconstituents of the stream outwardly, and means for heating a part ofthe bowl through which undeflected constituents of the stream pass, to atemperature above the ignition temperature of said undefiectedconstituents.

10. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, a manifold outside of thechamber in communication with the combustion space, a pressure pump, asuction conduit between the manifold and the pump, a pressure conduitbetween the pump and the feed spout, a valve-controlled conduit betweenthe chamber and the suction conduit, means for venting the chamber,means for introducing finely comminuted material into the stream, anaxially disposed open-ended circular bowl adjacent the discharge end ofthe feed spout, with the end of the bowl nearest the feed spout widerthan the discharge end of the feed spout and with the sides of the bowlconverging toward its other end, means for introducing gas containingoxygen into the stream through the sides of the bowl in directionssubstantially transverse to the flow of the stream through the feedspout to cooperate with said sides of the bowl to deflect lighterconstituents of the stream outwardly, and means for heating a part ofthe bowl through which undeiiected constituents of the stream pass, to atemperature above the ignition temperature of said undefiectedconstituents.

11. A burner comprising a structure forming a substantially closedchamber of circular cross section with a combustion space formedtherein, an axially disposed feed spout projecting into a part of thechamber remote from the combustion space, a manifold outside of thechamber in communication with the combustion space, a pressure pump, asuction conduit between the manifold and the pump, a pressure conduitbetween 8 l the pump and the feed spout, a valve-controlled conduitbetween the chamber and the suction conduit, a valveecontrolled ventfrom the chamber, means for introducing finely comminuted material intothe stream, an axially disposed openended circular bowl adjacent thedischarge end of the feed spout, with the end of the bowl near est thefeed spout wider than the discharge end of the feed spout and with thesides of the bowl converging toward its other end, means for introducinggas containing oxygen into the stream through the sides of the bowl indirections sul stantially transverse to the flow of the stream throughthe feed spout to cooperate with said sides of the bowl to deflectlighter constituents of the stream outwardly, and means for heating apart of the bowl through which undeflected constituents of the streampass, to a temperature above the ignition temperature of saidundeflected constituents.

12. A burner comprising a structure forming a substantially cylindricalbody with a cone-shaped portion at one of its ends together forming aclosed chamber with a combustion space therein, an axially disposedfunnel shaped feed spout projecting into a part of the chamber remotefrom the combustion space, a manifold surrounding the structure incommunication with the combustion space, means at the end of thestructure opposite the cone-shaped portion thereof forming an annularpassage in the form of a truncated cone axially alined with the body,the feed spout extending centrally from said passage with its smallerdischarge end innermost, a pressure pump outside the structure, asuction conduit between the manifold and the pump, a pressure conduitbetween the pump and said passage, means for venting the chamber, meansfor introducing finely comminuted material into the feed spout near itslarger end, an axially disposed open-ended circular bowl adjacent thedischarge end of the feed spout, with the end of the bowl nearest thefeed spout wider than the dischar e end of the feed spout and with thesides of the bowl converging toward its other end, means for introducinggas containing oxygen into the stream beyond the discharge end of thespout in directions substantially transverse to the flow of the streamthrough the feed spout to cooperate with said sides of the bowl todeflect lighter constituents of the stream outwardly, and means forheating a part of the bowl through which undefiected constituents of thestream pass, to a temperature above the ignition temperature of saidundeflected constituents.

13. A burner comprising a structure forming a substantially cylindricalbody with a cone-shaped portion at one of its ends together forming aclosed chamber with a combustion space therein, an axially disposedfunnel-shaped feed spout projecting into a part of the chamber remotefrom the combustion space, a manifold surrounding the structure incommunication with the combustion space, means at the end of thestructure opposite the cone-shaped portion thereof forming an annularpassage in the form of a truncated cone axially alined with the body,the feed spout extending centrally from said passage with its smallerdischarge end innermost, a pressure pump outside the structure, asuction conduit between the manifold and the pump, a valve-controlledconduit between the suction conduit and the chamber, a pressure conduitbetween the pump and said passage, a valve-controlled vent for thechamber, means for introducing finely comminuted material into the feedspout near its larger end, an axially disposed open-ended circular bowladjacent the discharge end of the feed spout, with the end of the bowlnearest the feed spout wider than the discharge end of the feed spoutand with the sides of the bowl converging toward its other end, meansfor introducing gas containing oxygen into the stream beyond thedischarge end of the spout in directions substantially transverse to theflow of the stream through the feed spout to cooperate with said sidesof the bowl to deflect lighter constituents of the stream outwardly, andmeans for heating a part of the bowl through which undeflectedconstituents of the stream pass, to a temperature above the ignitiontemperature of said undeflected constituents.

14. A burner comprising a structure forming a vertically disposedsubstantially cylindrical body with a cone-shaped portion at its lowerend forming a hopper, said body and hopper together forming a closedchamber with a combustion space therein, an axially disposedfunnel-shaped feed spout projecting into the upper part of the body, amanifold surrounding the structure in communication with the combustionspace, means near the upper end of the structure forming an annularpassage in the form of a truncated cone axially alined with the body,the feed spout extending centrally from said passage with its smallerdischarge end innermost, a pressure pump outside the structure, asuction conduit between the manifold and the pump, a pressure conduitbetween the pump and said passage, means for venting the chamber, meansfor introducing finely comminuted material into the feed spout near itslarger end, an axially disposed open-ended circular bowl adjacent thedischarge end of the feed spout, with the end of the bowl nearest thefeed spout wider than the discharge end of the feed spout and with thesides of the bowl converging toward its other end, means for introducinggas containing oxygen into the stream beyond the discharge end of thespout in directions substantially transverse to the flow of the streamthrough the feed spout to cooperate with said sides of the bowl todeflect lighter constituents of the stream outwardly, and means forheating a part of the bowl through which undeflected constituents of thestream pass, to a temperature above the ignition temperature of saidundeflected constituents.

15. A burner comprising a structure forming a vertically disposedsubstantially cylindrical body with a cone-shaped portion at its lowerend forming a hopper, said body and hopper together forming a closedchamber with a combustion space therein, an axially disposedfunnel-shaped feed spout projecting into the upper part of the body, amanifold surrounding the structure in communication with the combustionspace, means near the upper end of the structure forming an annularpassage in the form of a truncated cone axia1- 1y alined with the body,the feed spout extending centrally from said passage with its smallerdischarge end innermost, a pressure pump outside the structure, asuction conduit between the manifold and the pump, a valve-controlledconduit between the suction conduit and the chamber, a pressure conduitbetween the pump and said passage, a valve-controlled vent from thechamber, means for introducing finely comminuted material into the feedspout near its larger end, an

axially disposed open-ended circular bowl adjacent the discharge end ofthe feed spout, with the end of the bowl nearest the feed spout widerthan the discharge end of the feed spout and with the sides or the bowlconverging toward its other end, means for introducing gas containingoxygen into the stream beyond the discharge end of the spout indirections substantially transverse to the flow of the stream throughthe feed spout to cooperate with said sides of the bowl to deflectlighter constituents of the stream outwardly, and means for heating apart of the bowl through which undefiected constituents of the streampass, to a temperature above the ignition temperature of saidundeflected constituents.

16. A burner comprising a structure forming a vertically disposedsubstantially cylindrical body with a cone-shaped portion at its lowerend forming a hopper, said body and hopper together forming a closedchamber with a combustion space therein, an axially disposedfunnel-shaped feed spout projecting into the upper part of the body, amanifold surrounding the structure in communication with the combustionspace, means near the upper end of the structure forming an annularpassage in the form of a truncated cone axially alined with the body,the feed spout extending centrally from said passage with its smallerdischarge end innermost, a pressure pump outside the structure, asuction conduit between the manifold and the pump, a pressure conduitbetween the pump and said passage, means for venting the chamber, meansfor introducing finely comminuted material into the feed spout near itslarger end, an axially disposed open-ended circular bowl adjacent thedischarge end of the feed spout, with the end of the bowl nearest thefeed spout wider than the discharge end of the feed spout and with thesides of the bowl converging toward its other end, means for introducinggas containing oxygen into the stream beyond the discharge end of thespout in directions substantially transverse to the flow of the streamthrough the feed spout to cooperate with said sides of the bowl todeflect lighter constituents of the stream outwardly, and means forheating a part of the bowl through which undefiected constituents of thestream pass, to a temperature above the ignition temperature of saidundeflected constituents, said hopper being closed at its lower end andbeing providedwith an outlet port vertically spaced from saidclosed end.

THOMAS R. KOMLINE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 769,872 Ochwat Sept. 13, 19041,933,255 Godell Oct. 31, 1933 1,936,741 Wood Nov. 28, 1933 1,986,666Hardgrove Jan. 1, 1935 2,004,152 Badenhausen June 11, 1935 2,292,571Komline Aug. 11, 1942 FOREIGN PATENTS Number Country Date 6,175 GreatBritain Mar. 25, 1895 19,083 Great Britain Aug. 22, 1913

